Viessmann VITODENS 343-F WS4A Installation And Service Instructions Manual page 61

Further details regarding the individual steps
Setting the system details and functions
Special functions SF
Delivered condition: SF 5
Setting Description
range
SF 5 No special function
SF 6 No special function
SF 7 Suppressing re-heating by the compact boiler
Re-heating the DHW cylinder is suppressed as long as the solar
circuit pump is running.
In coding address " 67" (boiler control unit), enter a third set DHW
temperature (lower than the first set DHW temperature). The sup-
pression is lifted when the set value is not achieved by the solar
heating system.
SF 8 Additional function for DHW heating.
The additional DHW heating function (second set DHW tempera-
ture, e.g code "58:60") must be programmed at the boiler control
unit, and the fourth DHW phase must be enabled.
Commissioning, inspection, maintenance
(cont.)
4. Set the required value with a/b.
Confirm with d.
Note
After approx. 2 min, the display
reverts to the standard display, sub-
ject to no further adjustments or
confirmation being entered.
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